String.prototype.{match,search} should do only one RegExp brand check

test/mjsunit/es6/pattern-brand-check.js

Index: test/mjsunit/es6/pattern-brand-check.js
diff --git a/test/mjsunit/es6/pattern-brand-check.js b/test/mjsunit/es6/pattern-brand-check.js
new file mode 100644
index 0000000000000000000000000000000000000000..9b0c0111ef13b906955f47487990b23bd39e6801
--- /dev/null
+++ b/test/mjsunit/es6/pattern-brand-check.js
@@ -0,0 +1,54 @@
+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --harmony-regexp-subclass
+
+function createNonRegExp(calls) {
+  return {
+    get [Symbol.match]() {
+      calls.push("@@match");
+      return undefined;
+    },
+    get [Symbol.replace]() {
+      calls.push("@@replace");
+      return undefined;
+    },
+    get [Symbol.search]() {
+      calls.push("@@search");
+      return undefined;
+    },
+    get [Symbol.split]() {
+      calls.push("@@split");
+      return undefined;
+    },
+    [Symbol.toPrimitive]() {
+      calls.push("@@toPrimitive");
+      return "";
+    }
+  };
+}
+
+(function testStringMatchBrandCheck() {
+  var calls = [];
+  "".match(createNonRegExp(calls));
+  assertEquals(["@@match", "@@toPrimitive"], calls);
+})();
+
+(function testStringSearchBrandCheck() {
+  var calls = [];
+  "".search(createNonRegExp(calls));
+  assertEquals(["@@search", "@@toPrimitive"], calls);
+})();
+
+(function testStringSplitBrandCheck() {
+  var calls = [];
+  "".split(createNonRegExp(calls));
+  assertEquals(["@@split", "@@toPrimitive"], calls);
+})();
+
+(function testStringReplaceBrandCheck() {
+  var calls = [];
+  "".replace(createNonRegExp(calls), "");
+  assertEquals(["@@replace", "@@toPrimitive"], calls);
+})();